Chamber for blood treatment system,  use of the chamber, blood tubing system  and blood treatment system

ABSTRACT

The present invention relates to a chamber for a blood treatment system with at least one space defined by a chamber wall and with at least one blood inlet and with at least one inlet for a further fluid, which are connected with the space, wherein both the at least one blood inlet and the at least one inlet for the further fluid are formed on tube sections which protrude into the space of the chamber, wherein in the operating condition of the chamber the space of the chamber is at least partly filled with blood or with a mixture of blood and the further fluid or some other fluid and wherein at least one, preferably both or a plurality of the tube sections have a length such that the blood inlet and/or the inlet for the further fluid are located below the blood or fluid level in the chamber.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims priority to U.S. Provisional Application No.61/425,409 filed Dec. 21, 2010 and to German Patent Application No. 10015 895.5 filed Dec. 21, 2010, both of which are incorporated fully byreference herein.

FIELD OF THE INVENTION

The present invention relates to a chamber for a blood treatment systemwith at least one space defined by a chamber wall as well as with atleast one blood inlet and with at least one inlet for a further fluid,which are connected with the space.

BACKGROUND OF THE INVENTION

From the prior art it is known to provide a venous drip chamberdownstream of the dialyzer of a dialysis machine, which is part of theextracorporeal blood circuit. The function of this venous drip chamberis to ensure a rather bubble-free reinfusion of the patient bloodpurified in the dialyzer to the patient.

From the prior art it is furthermore known to introduce an infusionsolution, such as purified dialysate or a salt solution, into such dripchamber. Such supply can be effected in connection with the so-calledpredilution before the dialyzer and/or in connection with the so-calledpostdilution after the dialyzer.

FIG. 4 shows an embodiment known from the prior art in the form of a lidor headpiece of such venous drip chamber, on which a supply port 100 isarranged for the blood purified in the dialyzer.

Reference numeral 200 designates a supply port for said infusionsolution.

As can furthermore be taken from FIG. 4, it is known to introduce theblood into the chamber by means of a tube section 30, wherein the tubesection 30 includes an inlet 10 through which the blood is introducedinto the chamber, as is indicated by the arrow in FIG. 4.

Said infusion solution is introduced by means of the supply port 200,wherein the inlet for the infusion solution is located above the fluidor blood level in the chamber, which is designated with the referencenumeral 50. The infusion fluid drips or flows, as marked by the arrow inFIG. 4, onto the surface of the blood or the mixture of blood and theinfusion solution.

Such configuration of a drip chamber has the disadvantage that due tothe impingement of the infusion solution onto the surface of the fluidor blood present in the chamber the formation of microbubbles may occur,which can lead to an alarm condition being triggered and possibly thetreatment being stopped.

SUMMARY OF THE INVENTION

Thus, it is the object underlying the present invention to develop achamber as mentioned above to the effect that the formation ofmicrobubbles in the drip chamber is largely or completely prevented.

Accordingly, it is provided that both the at least one blood inlet andthe at least one inlet for the further fluid, such as an infusionsolution, are formed on tube sections which protrude into the space ofthe chamber. In contrast to the configuration according to the prior artas shown in FIG. 4 it thus is provided that the inlet for the infusionfluid and/or for the further fluid is formed on a tube section whichprotrudes into the space of the chamber in which the blood or themixture of blood and the infusion solution is contained.

In accordance with the present invention it is furthermore provided thatthe space of the chamber is at least partly filled with blood or with amixture of blood and a further fluid or with some other fluid and thatat least one of the tube sections has a length such that the blood inletand/or the inlet for the further fluid are located below the blood orfluid level in the chamber. In this way it is ensured that at least inthe operating condition of the chamber no dripping, not even from asmall height, onto the surface of the blood present in the chamber oronto the surface of the mixture of blood and infusion solution or otherfluid present in the chamber does occur. In accordance with a preferredaspect of the present invention, the blood and also the further fluidrather is introduced below the level of the blood or of the fluidpresent in the chamber. In this aspect the present invention thusrelates to a chamber for a blood treatment system, whose space is atleast partly filled with blood or with a mixture of blood and a furtherfluid or with some other fluid, wherein at least one of the tubesections has a length such that the blood inlet and/or the inlet for thefurther fluid are located below the fluid level or the blood level inthe space of the chamber.

In this way, it is possible to avoid dripping of the further fluid ontothe surface of the fluid or blood already present in the chamber andhence reduce the probability for the formation of microbubbles.

The term “tube section” should be interpreted broadly and comprises bothrigid and elastic elements which are suitable to pass blood or thefurther fluid into the chamber. Thus, for example solid, e.g. plastic,tube sections, hoses etc. are taken into consideration.

The diameter as well as the dimensions and the shape of these tubesections can largely be chosen as desired. For example, their inside andoutside diameter can be circular. However, configurations differenttherefrom are also comprised by the present invention. Furthermore, thepresent invention is not limited to the presence of exactly two tubesections. There can also be provided more than two tube sections, sothat the blood for example is introduced into the chamber through morethan one tube section and/or the further fluid is introduced throughmore than one tube section.

It is conceivable that at least one of the tube sections is arrangedsuch that in the operating condition of the chamber it extendsvertically or at an acute angle to the vertical. It thus is conceivablethat two or more tube sections are provided, which are arrangedsubstantially vertical and one of which includes one or more inlets forthe blood and/or the other one of which includes one or more inlets forthe further fluid.

The two tube sections can extend parallel or substantially parallel toeach other. However, an angular arrangement of the tube sectionsrelative to each other also is conceivable.

In a further aspect of the present invention it is provided that in theoperating condition of the chamber the space of the chamber is partlyfilled with blood or with a mixture of blood and the at least one fluidor some other fluid and that above the blood or fluid level an aircushion is disposed.

Furthermore, it can be provided that the tube sections have a differentlength or the same length. It is conceivable, for example, to design thetube section which carries the one or more inlets for the further fluidas long as or shorter or longer than the tube section which carries theone or more blood inlets.

It is particularly advantageous when the length of both tube sections issuch that the inlets for the blood and the further fluid are locatedbelow the fluid level in the chamber.

In a further aspect of the present invention at least one of the tubesections includes one or more blood inlets or one or more inlets for thefurther fluid. Thus, the present invention is not limited to the factthat each tube section only has exactly one inlet, but also comprisesthe case that two or more than two inlets are provided per tube section.

In a further aspect of the present invention it is provided that theblood inlet and/or the inlet for the further fluid is arranged in theend region of the tube section, which protrudes into the chamber.

Furthermore, it can be provided that at least one of the tube sectionsincludes a shell surface and an end surface protruding into the space ofthe chamber and that the at least one blood inlet and/or the at leastone inlet for the further fluid is at least partly or also completelyarranged in the shell surface. Due to this aspect of the presentinvention, a lateral introduction of the blood or further fluid, i.e. anintroduction from the side, is conceivable. In this aspect, the bloodand/or the further fluid thus is not introduced in a direction whichcoincides with the longitudinal axis of the tube section, but in adirection which extends at an angle thereto. It is conceivable that thisangle lies in the range between 30° and 150°, preferably in a rangebetween 60° and 120°, and particularly preferably in a range between 80°and 100° relative to the longitudinal axis of the tube section. If theangle is about 90°, for example, the blood thus flows first through theinterior of the tube section and then at right angles thereto out of thetube section through the inlet into the chamber.

In a further aspect of the present invention it is provided that atleast one of the tube sections includes a plurality of blood inlets or aplurality of inlets for the further fluid. This plurality of inlets canbe arranged such that the blood flows from the tube section into thechamber in different directions. The same can apply to said furtherfluid. It is conceivable that the two inlets are arranged such that theblood or the further fluid flows out of the tube sections on oppositesides, so that opposite flow directions are obtained.

It is furthermore conceivable that the plurality of inlets are arrangedat the same level, i.e. in the case of vertical tube sections at thesame vertical position of the tube sections, and/or that the pluralityof inlets have an identical size or also different sizes.

Furthermore, it can be provided that at least one of the tube sectionshas a wall in its end region protruding into the space of the chamberand that the at least one inlet is located adjacent to this wall. Thus,this wall can form the end of the tube section protruding into thespace. Adjacent to this wall one or more inlets for the blood or for thefurther fluid can be located.

As an alternative to the above described embodiment with two inlets pertube section it is of course also conceivable to form more than twoinlets, for example three or four inlets per tube section.

These inlets can be uniformly spaced in circumferential direction aroundthe respective tube section. A non-uniform distribution also isconceivable.

Said introduction of the blood or of the further fluid by means of aplurality of inlets spaced from each other in circumferential directioninvolves the advantage that a vortex formation inside the chamber iseffectively counteracted, which in turn involves the advantage that theoccurrence of microbubbles is largely or completely prevented.

The one or more inlets for the blood or the one or more inlets for thefurther fluid can be arranged such that the blood or the further fluidis introduced in radial direction of the chamber or directed towards thechamber wall or also in tangential direction of the chamber or incircumferential direction or also in a direction between these twodirections.

Furthermore it can be provided that the tube sections are spaced fromeach other, so that separate inlets for blood on the one hand and forthe further fluid on the other hand are present. Furthermore it can beprovided that the chamber includes a base body and a lid or headpiececlosing the base body and that the tube sections are arranged on the lidor headpiece and preferably extend through the lid or headpiece. The lidor headpiece can be firmly connected with the base body or also bereleasable from the base body. In the case of a fixed design it isconceivable to design the base body and the lid or headpiece in onepiece.

The present invention furthermore relates to the use of a chamber in ablood treatment system. Preferably the chamber is used as a venouschamber which is arranged downstream of a dialyzer.

In the operating condition of the chamber the space of the chamber canat least partly be filled with blood or with a mixture of blood and thefurther fluid or some other fluid and at least one of the tube sectionscan have a length such that the blood inlet and/or the inlet for thefurther fluid is located below the blood or fluid level in the chamber.As already explained above, the particularly preferred aspect of thepresent invention can be realized in that dripping of both the blood andthe further fluid onto the surface of the blood present in the chamberor onto the surface of the fluid present in the chamber is prevented.

In a further aspect of the present invention it is provided that in theoperating condition of the chamber the space of the chamber is partlyfilled with blood or with a mixture of blood and the further fluid orsome other fluid and that above the blood an air cushion is disposed.

Furthermore, it can be provided that in the operating condition of thechamber at least one of the tube sections extends vertically or at anacute angle to the vertical.

As already explained above, it is advantageous when the one or moreinlets for the blood and/or for the further fluid are formed on the tubesection such that the blood and/or the further fluid exits from the tubesection at an angle to the longitudinal axis of the tube section. Thisangle can lie for example in the range between 30° and 150°, preferablyin a range between 60° and 120°, and particularly preferably in a rangebetween 80° and 100°.

At least one of the tube sections can have a plurality of inlets whichare arranged on the tube section such that the blood and/or the furtherfluid is discharged from the respective tube section in at least twodifferent directions. In this way, too, the formation of vortices in thechamber and hence also the occurrence of microbubbles can largely orcompletely be prevented.

The further fluid can be an infusion solution, in particular a dialysissolution or a salt solution, such as a sodium chloride solution. Thesame is mixed with blood in the space of the chamber and then thismixture is supplied to the patient.

The present invention furthermore relates to a blood tubing system withat least one chamber. It can be provided that the blood tubing system isprovided with a predilution port and/or with a postdilution port andthat one or both of these ports are in fluid connection with the tubesection for the further fluid or are connectable to form a fluidconnection.

The present invention furthermore relates to a blood treatment systemwith at least one chamber or with at least one blood tubing system.

In an advantageous aspect of the present invention it is provided thatthe blood treatment system is a dialysis machine. The dialysis machinecan be configured to perform a hemodialysis, a hemofiltration or also ahemodiafiltration with said machine.

Furthermore, it can be provided that the further fluid is provided bythe dialysis machine.

BRIEF DESCRIPTION OF THE DRAWINGS

Further details and advantages of the present invention will beexplained in detail with reference to an embodiment illustrated in thedrawing, in which:

FIG. 1 shows a perspective representation of a lid of a chamber of thepresent invention in a view obliquely from below.

FIG. 2 shows a sectional representation through a tube section withinlets for blood or the further fluid.

FIG. 3 shows a schematic top view of the arrangement of FIG. 1 withindicated flow directions for the blood and for the further fluid.

FIG. 4 shows a side view of a lid of a venous drip chamber from theprior art.

DETAILED DESCRIPTION OF THE DRAWINGS

In a perspective view obliquely from below, FIG. 1 shows a head or lidregion 60 of a venous chamber of an extracorporeal blood circuit of adialysis machine.

Reference numeral 100 designates the supply port for the blood, andreference numeral 200 designates the supply port for the infusionsolution. The supply port 100 is connected with the extracorporeal bloodcircuit. Through the supply port 100, the blood purified in the dialyzerflows into the venous chamber of the present invention, whose lid orheadpiece 60 is shown in FIG. 1.

The supply port 200 for the infusion solution is connected with asuitable source for the infusion solution, such as dialysate, a sodiumchloride solution, etc. Through this port 200, the infusion solution issupplied to the chamber. In the illustrated embodiment, this supplytakes place downstream of the dialyzer, so that there is a postdilution.

In principle, however, the present invention is not limited thereto, butprovides for using a chamber also in the region of the predilution.

In FIG. 1, reference numeral 50 designates the blood level or the levelof the fluid present in the chamber. This fluid consists either of bloodonly or of a mixture of blood and said infusion fluid or of some otherfluid. As can furthermore be taken from FIG. 1, the supply port 100preferably is firmly or integrally connected with the tube section 30,and the supply port 200 preferably is firmly or integrally connectedwith the tube section 40 extending parallel thereto. Both tube sections30, 40 are spaced from each other, as can be taken from FIG. 1. Thesupply ports 100, 200 can be an integral part of the tube sections 30,40 or be connected with the same in a suitable way. It is alsoconceivable that the tube sections 30, 40 and/or the supply ports 100,200 are integral parts of the lid or of the headpiece 60 of the chamberor are connected with the same in some other way, for example insertedinto the same.

Reference numeral L designates the longitudinal axes of the two tubesections 30, 40 which protrude into the space of the chamber which onthe head side is closed off by the headpiece 60 or by the lid 60.

As can furthermore be taken from FIG. 1, each of the tube sections 30,40 includes an inlet 10, 21 in its shell surface 31, 41, through whichblood on the one hand and the infusion fluid on the other hand gets intothe fluid or blood already present in the chamber.

FIG. 1 furthermore shows that both the inlet 10 for the blood and theinlet 21 for the further solution or for the infusion fluid is locatedbelow the level 50 of the fluid or blood already present in the chamber.FIG. 1 furthermore shows that the inlets 10, 21 are not arranged in thedownwardly pointing end region 32, 42 of the tube sections 30, 40, butare arranged at least also or exclusively laterally, so that the bloodor the further fluid exits from the tube sections 30, 40 laterally or atleast also in a lateral direction.

In accordance with the present embodiment it thus is provided that boththe inlet for the infusion solution and the inlet for the blood islocated below the level 50 of the blood already present in the chamberor of the mixture of blood and infusion solution or some other fluid.

Furthermore, it is provided in accordance with the present embodimentthat separate inlets for blood on the one hand and for the furthersolution on the other hand are present.

As can furthermore be taken from FIG. 1, the tube section 40 whichcarries the inlet for the further solution is formed slightly shorterthan the tube section 30 which carries the inlet 10 for the blood. Inprinciple it is also conceivable to design these two tube sections 30,40 of identical length or to provide the height or position of therespective inlets 10, 21 at the same level or to design the tube section40 longer than the tube section 30.

FIG. 2 shows a sectional representation through the tube section 30 oralso through the tube section 40. As can be taken from FIG. 2, the tubesection 30, 40 is an integral part of the lid and preferably formedintegrally with the same. Thus, an integrated infusion port can berealized by the present invention.

From FIG. 2 it can furthermore be taken that both the tube section 30for supplying blood and the tube section 40 for supplying the furtherfluid is each formed with two inlets 10, 11; 20, 21 which directlyadjoin the end-side wall 32, 42. As can also be taken from FIG. 3, theseinlets are arranged opposite each other, which results in that the bloodor the further solution exits from the respective tube section 30, 40 onopposite sides and enters the fluid already present in the chamber. Thiscan be taken for example from FIG. 3. Here, reference numeral 30designates the tube section for supplying blood, and reference numerals10, 11 designate the inlets for blood. These inlets are arranged at theside of the tube section 30, i.e. laterally and in an opposed manner,which results in that, as shown in FIG. 3, the blood is discharged fromthe tube section 30 in opposed, i.e. in opposite directions.

This applies to the formation of the tube section 40 for supplying thefurther fluid. Here as well two opposed inlets 20, 21 are provided,which likewise have a different size. As shown in FIG. 3, the flowdirections of the blood and of the further fluid are parallel whenflowing out of the tube sections 30 and 40. However, a non-paralleloutflow of blood on the one hand and of the further solution on theother hand also is comprised by the present invention.

In principle, the present invention also comprises the case that therespective inlets 10, 11 and 20, 21 are designed with an identical size.The inlets 10, 11 and 20, 21 can be arranged on the tube section at anidentical level or also at different levels.

As can furthermore be taken from FIG. 3, the inlets are arranged such inthe embodiment shown here that the inflow direction of the blood or ofthe further fluid is neither radial relative to the shell surface of thehousing or of the lid of the chamber, which is cylindrical or circularin cross-section, nor tangential. Rather, it is provided here that theinflow direction of the blood or of the further fluid is effected in adirection which lies between the radial and the tangential direction. Bymeans of this aspect of the present invention a better intermixing ofthe blood and of the infusion fluid is achieved and there is noturbulent effect which would lead to the level descending in the middleof the chamber and ascending at the sides thereof. Rather, it isachieved by the illustrated embodiment that the fluid level 50 or thesurface of the fluid in the chamber remains largely flat, so that thevortex formation is largely or completely prevented, which in turnresults in the fact that the occurrence of microbubbles or foam isprevented.

The venous drip chamber shown in FIGS. 1 to 3 with separate inlets forblood and the further fluid and with the special design of the inletsfor blood and fluid at the tube section involves the advantage thatneither a dripping of blood and/or the further solution onto the surfaceof the fluid or blood present in the chamber is effected as well as thefurther advantage that a vortex formation and hence a foam formation ora formation of microbubbles is largely or completely prevented. The oneor more tube sections 30, 40 can be manufactured by the method ofinjection molding. In this method, providing the further openings 11, 21involves certain advantages as regards the stability and the simplicityof the performance of the method. Thus, it is preferably provided thatthe lid or the headpiece 60 as a whole or at least the tube sections 30,40 are manufactured by the method of injection molding.

The chamber of the present invention in particular is advantageouslyapplicable in connection with the hemodiafiltration postdilutiontreatment and preferably in connection with the online HDF postdilution.

Thus, the supply port 200 preferably is a port for an infusion solutionwhich is supplied to the blood after purifying the same in the dialyzer.

1-28. (canceled)
 29. A chamber for a blood treatment system comprising:at least one space defined by a chamber wall; at least one first inletfor a first fluid; and at least one second inlet for a second fluid,wherein the at least one first inlet and the at least one second inletare connected with the at least one space, wherein the at least onefirst inlet is formed on a first tube section that protrudes into thespace of the chamber, said first tube section having a firstlongitudinal axis, wherein the at least one second inlet is formed on asecond tube section that protrudes into the space of the chamber, saidsecond tube section having a second longitudinal axis, wherein in anoperating condition, the space of the chamber is at least partly filledup to a fluid level with the first fluid or with a mixture of the firstfluid and the second fluid, and wherein at least one of the first tubesection and the second tube section has a length such that the firstinlet, the second inlet, or both are located below the fluid level inthe chamber.
 30. The chamber according to claim 29, wherein in theoperating condition, at least one of the first tube section and thesecond tube section extends parallel to a vertical axis or at an acuteangle to the vertical axis.
 31. The chamber according to claim 29,wherein in the operating condition, the first tube section and thesecond tube section extend parallel or substantially parallel to eachother.
 32. The chamber according to claim 29, wherein in the operatingcondition, an air cushion is disposed above the fluid level.
 33. Thechamber according to claim 29, wherein the first tube section and thesecond tube section have different lengths.
 34. The chamber according toclaim 29, wherein at least one of the first tube section and the secondtube section includes a plurality of inlets.
 35. The chamber accordingto claim 29, wherein the first inlet, the second inlet, or both arearranged in an end region of the first tube section or the second tubesection that protrudes into the chamber.
 36. The chamber according toclaim 29, wherein at least one of the first tube section and the secondtube section comprises: a shell surface and an end surface protrudinginto the space of the chamber, wherein the at least one first inlet, theat least one second inlet, or both are at least partly arranged in theshell surface.
 37. The chamber according to claim 29, wherein the firstinlet, the second inlet, or both are formed in the first or second tubesection such that the first or second fluid exits from the first orsecond tube section at an angle to the first or second longitudinalaxis.
 38. The chamber according to claim 37, wherein the angle lies inthe range between 30° and 150°.
 39. The chamber according to claim 29,wherein both the first and second tube sections includes a plurality ofinlets.
 40. The chamber according to claim 39, wherein the plurality ofinlets are arranged on opposite sides of the respective tube section,the plurality of inlets are arranged at the same level of the respectivetube section, the plurality of inlets have an identical size, theplurality of inlets have different sizes, or any combination thereof.41. The chamber according to claim 29, wherein at least one of the firstor second tube sections has a wall in an end region protruding into thespace of the chamber and the at least one first or second inlet islocated adjacent to the wall.
 42. The chamber according to claim 29,wherein the first and second tube sections are spaced from each other,so that separate inlets are present for the first fluid and for thesecond fluid.
 43. The chamber according to claim 29, wherein the chamberfurther comprises: a base body; and a lid or headpiece closing the basebody, wherein the first and second tube sections are arranged on the lidor headpiece and extend through the lid or headpiece.
 44. A method ofusing a venous chamber in a blood treatment system, wherein the chambercomprises: at least one space defined by a chamber wall; at least onefirst inlet for a first fluid; and at least one second inlet for asecond fluid, wherein the at least one first inlet and the at least onesecond inlet are connected with the at least one space, wherein the atleast one first inlet is formed on a first tube section that protrudesinto the space of the chamber, said first tube section having a firstlongitudinal axis, wherein the at least one second inlet is formed on asecond tube section that protrudes into the space of the chamber, saidsecond tube section having a second longitudinal axis, the methodcomprising: at least partly filling the space of the chamber with bloodor with a mixture of blood and the second fluid up to a fluid level,wherein at least one of the first or second tube sections have a lengthsuch that the first inlet, the second inlet, or both is located belowthe fluid level in the chamber.
 45. The method according to claim 44,further comprising disposing an air cushion above the fluid level. 46.The method according to claim 44, wherein at least one of the first orsecond tube sections extends parallel to a vertical axis or at an acuteangle to the vertical axis.
 47. The method according to claim 44,wherein the at least one first and second inlets are formed on the firstand second tube sections such that the fluid exits from the first orsecond tube section at an angle to the first or second longitudinalaxis.
 48. The method according to claim 47, wherein the angle lies inthe range between 30° and 150°.
 49. The method according to claim 44,wherein at least one of the tube sections include a plurality of inletsarranged on the tube section such that the blood and the second fluidare discharged from the respective tube sections in at least twodifferent directions.
 50. The method according to claim 44, wherein thesecond fluid is an infusion solution.
 51. A blood tubing systemcomprising: a chamber for a blood treatment system comprising: at leastone space defined by a chamber wall; at least one first inlet for afirst fluid; and at least one second inlet for a second fluid; and apredilution port, a postdilution port, or both, wherein the at least onefirst inlet and the at least one second inlet are connected with the atleast one space, wherein the at least one first inlet is formed on afirst tube section that protrudes into the space of the chamber, saidfirst tube section having a first longitudinal axis, wherein the atleast one second inlet is formed on a second tube section that protrudesinto the space of the chamber, said second tube section having a secondlongitudinal axis, wherein in an operating condition, the space of thechamber is at least partly filled up to a fluid level with the firstfluid or with a mixture of the first fluid and the second fluid, whereinat least one of the first tube section and the second tube section has alength such that the first inlet, the second inlet, or both are locatedbelow the fluid level in the chamber, wherein the predilution port, thepostdilution port, or both are in fluid connection with the second tubesection.
 52. The blood tubing system according to claim 51, wherein theblood treatment system is a dialysis machine.
 53. The chamber accordingto claim 29, wherein both of the first and second tube sections have alength such that the first inlet and the second inlet are located belowthe fluid level in the chamber.
 54. The chamber according to claim 29,wherein the first fluid is blood.
 55. The chamber according to claim 29,wherein the first tube section and the second tube section have the samelength.
 56. The chamber according to claim 37, wherein the angle lies inthe range between 60° and 120°.
 57. The chamber according to claim 37,wherein the angle lies in the range between 80° and 100°.
 58. The methodaccording to claim 47, wherein the angle lies in the range between 60°and 120°.
 59. The method according to claim 47, wherein the angle liesin the range between 80° and 100°.
 60. The method according to claim 44,wherein the second fluid is a dialysis solution or a salt solution.